The "spin and throw" method is effective! Spin the cake on your fingertips and throw (or press on) with your other hand over a giant bowl. Scoop up some more, press on, and spin the cake again. Repeat until covered.

I put down parchment paper under cake. Then i pick up handful of whatever and press on cake(like you would do coconut,etc.) I then turn the cake and go on around. The parchment paper catches what has dropped and then you save them.hth